Bowling pin and method of making same



June 21, 1966 J. MEDNEY BOWLING PIN AND METHOD OF MAKING SAME Filed June 26, 1961 INVENTOR JONAS MEDNEY .fiumM H- 2 GRIND (OPTIONAL) MOLD IN CAVITY MO SHAPE (a) DOCTOR BLADE CURE ATTO R N EY present invention.

United States Patent 0 3,257,113 BOWLING PIN AND METHOD OF MAKING SAME Jonas Medney, Oceanside, N.Y., assignor to Koppers Company, Inc., a corporation of Delaware Filed June 26, 1961, Ser. No. 119,632 5 Claims. (Cl. 273-82) This invention relates to an improved bowling pin and method of making same.

The term bowling pin as employed herein,'is intended to encompass duck pins, ten pins, candle pins, and other like devices.

Bowling pins in current use are made of laminated hard wood stock which is turned in a lathe to shape and then coated with alayer of synthetic resin. The pins in a busy alley last about three months, after which time they must be replaced. Since a typical automatic pin-setting alley employs twenty pins, it will be appreciated that the life. of a pin is ofgreat economic importance to the operation of the alley. In the past, many attempts have-been made to reinforce bowling pins. However, as far as is presently known, none has proven successful prior to the The reinforcing process employed must be economically feasible, and must not interfere with the normal playing qualities of the pin.

'One of the unusual problems in making a satisfactory bowling pin is that the pin must produce a satisfactory sound when struck by the bowling ball. Players are quick to note the difference in tone between a new pin and an old battered pin. Therefore, in addition to having a satisfactory tone, it is desirable that the tone sound consistently like that provided by a new pin of the conventional type. Pins ingeneral must conform to the measurement specifications established by bowling associations in order to be accepted for tournament play. The prior art wood pin'suifers from a tendency to change its bounce effect with use. 'As the pin is repeatedly hit by the bowling ball it becomesdenser and as a result, an old pin does not react with the same sound as a new pin. On the other hand, the improved pin of this invention provides uniform bounceresponse over its useful life. As explained more fully hereinafter, the pin of this invention provides a high pitched vibration when struck, having a sound effect like that produced by a new pin. The process of this invention fulfills these requirements.

Briefly stated, the invention comprises the provision of a resin bonded, filament wound layer of a continuous filament having a high tensile strength such as glass fibre, steel wire, nylon, Orlon and other like materials. The

winding is applied under high tension at substantially right angles to the major axis of the pin.

Accordingly, it is an object of this invention to provide an improved bowling pin.

It is another object of this invention to provide a reinforced bowling pin.

It is a further object of this invention to'provide a bowling pin having a filament wound reinforcement.

It is a different object of this invention to provide a bowling pin yielding a high pitched tone when struck.

Still another object of this invention is to provide a bowling pin characterized by a long life.

Still a further object of this invention is to provide a filament wound bowling pin.

Still another object of this invention is to provide a bowling pin reinforced by a glass fibre winding bonded with an epoxy resin.

These and still further objects and advantages will, in part, become obvious and will, in part, be pointed out with particularity as the following description proceeds taken in conjunctionwith the accompanying drawing.

In the drawing: I

FIG. 1 shows partially broken away a preferred embodiment of this invention.

FIG. 1a is a vertical cross-section of the lower portion of the pin of FIG. 1 showing an alternative embodiment.

FIG. 2 is apartially sectioned elevation of an alternate embodiment of this invention.

FIGS. 3 and 4 are vertical sections showing details of alternate methods of inlaying a winding.

FIG. 5 is a flow chart showing the process of this invention.

FIG. 6 is a fragmentary elevation of a conventional laminated bowling pin at the moment of impact.

Referring now to FIG. 1, there is shown a typical bowling pin made in accordance with the present invention. The pin ismade of wood and is turned about major axis 10 in the normal fashion with the exception that at the neck 11 adjacent to head 12, the diameter is smaller than that of the conventional pin. The subsequent fibre layers will bring the diameter to the standard diameter. Body portion 14 maybe further modified by forming a recess in belly portion 16 for a filament winding. The recess at the neck 11 and belly 16 may be arcuate, as shown in FIG. 1, or modified, as shown in FIG. 3; or, in the alternative, a flat, as shown in FIG. 4, may be provided which is built up by a resin impregnated winding 22. It is to be understood that a recess is not essential but merely a section of reduced diameter to accommodate the winding.

The base 18 of the pin is provided with a nylon insert 20. This nylon insert is conventional in the art. There is shownin FIG. 1a a preferred modification of the pin wherein the nylon insert is replaced by a resin bonded, filament-wound structure 23.

The use of high tensile strength, high modulus of elasticity filaments provides high impact resistance in the direction of the load seen by the bowling pin upon impact.

An important feature of the invention is that it provideswindings on either side of the center of gravity of the pin so that the weights of the windings can be placed against each other, and also permits the pin to be made more hollow than the conventional pin, as by providing a central bore.

Conventional pins are made by turning down a laminated hardwood blank. The outer laminations 38 extend to the vicinity of the neck portion. Upon impact by bowling ball 39, the top of the lamination 38 tends to deflect outwardly and separates from core 40, as shown somewhat exaggerated by the dashed lines 41 in FIG. 6. The device of this invention prevents this undesired effect from occurring.

While it has been found adequate to provide the winding at the neck 11 and belly 16, it may be desirable for some purposes to completely wind the entire periphery of the pin and eliminate the conventional vinyl plastic layer 26 commonly employed in coating pins. A pin 29 made in accordance with this embodiment is shown in FIG. 2.

In FIG. 5, a method of carrying out the process is shown. The wood bowling pin is mounted on a conventional helical winding machine and rotated. Simultaneously, a bundle of fibres 32 is fed from supply roll 34 through a bath of resin 36 and wound onto pin 30. A suitable fibre is a glass filament having a diameter of 0.00038" and wound with 204 filaments to the end, with many ends simultaneously in a flat band. Maximum tension is maintained on the bundle, the amount of tension being limited only by the breaking point of the bundle and the crushing point of the wood. By way of example, for glass fibre, if hard maple is employed for the pin, a tension of about lb. on a 204-filament bundle of 0.00038" diameter filaments is suitable. Tension in the range 0.1 to 1.0 lb. per glass fibre bundle of the type described is suitable. As the wall thickness increases, the tension should be relaxed slightly to prevent the inner layers from being placed in compression. Such variation is within the skill of the average filament winding operator.

After the winding operation is completed, the article is placed in an oven and cured. In some cases, it is desirable to finish the pin by a subsequent grinding operation to conform the contour of the pin with a standard template.

If the entire pin surface is wound over its entirety with resin impregnated filament, then the resin may be cured (step b) and. the pin ground to the desired contour (step c).

In place of the grinding ope-ration (step c), a doctor blade (step 2), having the desired contour, is positioned against the pin which is rotated and the resulting shaped pin cured; or, the alternative procedure (step 1) may be followed in which cure is carried out in a conventional matched cavity mold so that the final product is of the desired configuration. It is to be noted that the pin may be colored by employing suitable pigments in the resin.

Where only the neck and body portions are filamentwound, the entire pin may he resin coated (step d) and shaped by the procedure of steps e and g or f. If the resin coating step is carried out by spraying or dipping, then in some instances, the subsequent steps may not be necessary. Such finishing techniques are well known to industry. a

A near vertical wrap is preferred, that is, a wrap wherein the windings are substantially at right angles to the major axis of the pin.

A preferred resin for this purpose is a plasticized epoxy resin. A typical formula for this resin is as follows:

Parts by weight Epoxy resin (Shell Chemical Corp. Epon 826) 100 Nadic methyl anhydride 90 Benzol dimethylamine 2 Plasticizer A 10 Total 20-2 Plasticizer A above is a glycidyl ester of mixed dimers and trimers of long chain unsaturated fatty acids having an epoxide value of 0.242 equiv./ 100 grams of resin and a hydroxyl value of 0.019 equiv./ 100 grams of resin.

The method of making this plasticizer is disclosed in U.S. Patent 2,940,986.

Epoxy resins are condensation products of epichlorohydrin and bisphenol A. The particular resin used in the example was a low viscosity liquid glycidyl ether bisphenol-epichlorohydrin, with an epoxide equivalent of from about 0.5 gram/ 100 grams of resin. Other epoxy resins may be employed, their selection being a matter of choice from lists of commercially available products having suitable properties. The epoxy resin may be plasticized with other materials, for example, T-hiokol Chemical Corp. LP-3 which is mercaptan terminated, long chain aliphatic polymer containing disulphide linkages having an average molecular weight of 1000. Suitable formulations are fully described in the Thiokol Chemical Corp. brochure Liquid Polymer/Epoxy Resins Systems (May 1960). Still other plasticizers are commercially available.

A number of resinous compositions have been used with success in fabricating the novel reinforced. plastic pin of this invention. Although epoxy resins are generally preferred because of excellent adhesion to glass, excellent mechanical and age-resistant properties, and freedom from shrinkage and evolution of volatiles upon curing, phenolic, polyester, melamine, novolacs or other suitable resins may be employed in order to reduce the cost of the artiole. There is also commercially available glass fibre bundies preimpregnated with a coating of B stage resin.

This preimpregnated material may be used in the same way.

There are several unobvious advantages of the invention. For example, there is a rapidly decreasing supply of hard woods suitable for producing pins. This invention permits the use of a wood blank about 4;" less in diameter than conventional pins, thus providing a saving in scarce material and extending the available supply. Further, this invention permits the use of lumber meeting less stringent specifications, thus broadening the available supply and permitting the use of less expensive lumber types than heretofore.

Another feature of this invention is that it permits the reworking of old pins. In this case, the old pin is shaved down to the shape suitable for the type of resin-bonded filament wrapping to be added and the pin reinforced in accordance with the invention. In rebuilding old pins it is preferred to use the complete covering, as shown in FIG. 2.

There are many suitable fibres for the purposes of this invention including, by way of example, glass, nylon, rayon, polypropylene, etc. Other suitable fibres will be obvious to those skilled in the art upon reading the foregoing specification.

Having disclosed the best embodiment of the invention presently contemplated, what is claimed is:

1. In a wooden bowling pin comprising a head, a neck, a base and an arcuate portion having a belly section, the combination of a glass fiber filament helically wound over said belly section; said filament being wound in concentric layers of uniform tension, and synthetic resin bonding together the adjacent turns of the filament.

2. The bowling pin of claim 1 wherein turns of said filament winding are oriented substantially at right angles to the major axis of the bowling pin.

3. The bowling pin of claim 1 including a resin bonded helically wound, glass fiber filament covering said neck section.

4. The bowling pin of claim 3 wherein said base comprises a resin bondedhelically wound, glass fiber filament. 5. The method of reinforcing and finishing a bowling pin which includes the steps of:

(a) turning an annular groove in the ball contact zone of the pin;

(b) winding an uncured resin coated glass fiber filament under tension to at least a height consistent with the contours of a standard bowling pin;

(c) curing said resin;

(d) turning the pin including the resin and filament to standard bowling pin contours;

(e) coating the turned pin with resin coating;

(f) shaping the pin to standard bowling contours; and

(g) curing said resin coating.

References Cited by the Examiner UNITED STATES PATENTS 2,110,183 3/1938 Tu-bbs 273--65 2,273,200 2/ 1942 Holt. 2,341,926 2/ 1944 Lauby. 2,352,872 7/1944 Voit et al. 273 -65 2,517,116 8/1950 Klinger 273-82 2,535,033 12/1950 Bergere 27382 2,594,693 4/1952 Smith. 2,738,977 3/1956 Riley 273-82 2,813,818 11/1957 Pearson. 1 2,876,011 3/1959 Hunt 273-82 2,978,375 4/1961 Grawey 273-82 X 2,980,158 4/1961 Meyer. 3,098,655 7/1963- Martin 273-82 3,135,639 6/1964 Bilodeau 273-82 X OTHER REFERENCES The ABC News for May 1955, 2 pages.

RICHARD c. PINKHAM, Primary Examiner. 

1. IN A WOODEN BOWLING PIN COMPRISING A HEAD, A NECK, A BASE AND AN ARCUATE PORTION HAVING A BELLY SECTION, THE COMBINATION OF A GLASS FIBER FILAMENT HELICALLY WOUND OVER SAID BELLY SECTION; SAID FILAMENT BEING WOUND IN CONCENTRIC LAYERS OF UNIFORM TENSION, AND SYNTHETIC RESIN BOUNDING TOGETHER THE ADJACENT TURNS OF THE FILAMENT.
 5. THE METHOD OF REINFORCING AND FINISHING A BOWLING PIN WHICH INCLUDES THE STEPS OF: (A) TURNING AN ANNULAR GROOVE IN THE BALL CONTACT ZONE OF THE PIN; (B) WINDING AN UNCURED RESIN COATED GLASS FIBER FILAMENT UNDER TENSION TO AT LEAST A HEIGHT CONSISTENT WITH THE CONTOURS OF A STANDARD BOWLING PIN; (C) CURING SAID RESIN; (D) TURNING THE PIN INCLUDING THE RESIN AND FILAMENT TO STANDARD BOWLING PIN CONTOURS; (E) COATING THE TURNED PIN WITH RESIN COATING; (F) SHAPING THE PIN TOSTANDARD BOWLING CONTOURS; AND (G) CURING SAID RESIN COATING. 